This application is for the transfer of the research study, Study of Development of Atypical Sex Roles in Children, from the University of California at Los Angeles to the State University of New York at Stony Brook. Following is the description of this research project as it was provided in the original application. It should be noted, since the project is now in its second year that some of the proposed work as described below is already underway. The proposed study is an expansion of research on atypical sex-role development in children. To date a sample of 40 very feminine boys, age 3-10, and their families, has been generated. These boys strongly prefer the dress, toys, games, and companionship of girls, role-play exclusively as females, and assert they are, or will become girls. A smaller sample of 6 very masculine girls has also been generated. Their behavior is the converse of that of the feminine boys. Psychological testing and interview data have been gathered on these children and their parents, and on a smaller group of control families with children who show typical sex-role development. Pilot efforts at effecting behavioral changes in some of these children have begun. Expansion of the project will include physiological data collection, including electroencephalographic analysis, and plasma gonadal hormone levels on the children, additional research procedures for assessing family interaction, new techniques for attempting behavioral change, expansion or the control family population, and adding to the sample of masculine girls. Continuation of research on the current sample will include follow-up evaluations and further analysis of previously gathered data. This study hopes to provide information on psychosexual differentiation in children by contrasting those with markedly atypical development with children whose sex-role behavior is culturally typical. As a longitudinal study, it hopes to correlate early atypical sex-role adoption with adult sexual behavior.